Chemistry
A 1.50- gas sample at 735 and 25.0 contains 5.00 radon-220 by volume. Radon-220 is an alpha-emitter with a half-life of 55.6 . How many alpha particles are emitted by the gas sample in 4.00 minutes?July 29, 2012

AP CHEM
Hello, I'm working these homework questions out; however it is a series of questions and without one step correctly completed, it's nearly impossible to get the others. I posted my work and commented where I need assistance. Thank you so much in advance!!! Potassium ...April 17, 2008

bio?
hypothyroidsm affects body temperature, which in turn could also influence sperm production. if the body gets too warm sperm production may decrease. i'm not sure if that's the answer you need, hypothyroidism also affects changes in appetite/weight.April 8, 2008

CHEM-KSP/KA PROBLEMS
really don't quite understand how to set up a caluculation to figure out whether a precipitate will form and i'm struggling with the second half too! When 25.75 mL of 0.00826 M lead II nitrate is mixed with 75.10 mL of 0.0183 M sodium chloride solution, will a ...April 8, 2008

Ksp/Ka Questions-Chem
I really don't understand how to set this up. Any help is really appreciated! I really don't quite understand how to set up a caluculation to figure out whether a precipitate will form and i'm struggling with the second half too! When 25.75 mL of 0.00826 M lead II ...April 8, 2008

u.s.history
The soviet union felt threatened by the missiles the U.S. had placed in Turkey and Greece and wanted a missile base closer to the United States. I found this from a website:The real-life and human story of what took place in the waters around Cuba between October 22 and 28 of ...April 8, 2008

u.s.history
13 days is the length of the cuban missile crisis. there's an awesome movie out there that really describes the situation and its not a boring history documentary. check it out if you can, its called thirteen days. it really helped me understand the crisis better.April 8, 2008